Transfer entropy-based multi-terminal DC transmission line protection method

Abstract

The invention discloses a transfer entropy-based multi-terminal DC transmission line protection method, which comprises the following steps of (S1) collecting positive and negative current of a multi-terminal DC transmission line on a DC circuit breaker of a fault point; (S2) calculating a transfer entropy drop of the positive and negative current; (S3) judging whether a fault appears or not according to the transfer entropy drop and a transfer entropy criterion; (S4) calculating zero-module current on the DC circuit breaker of the fault point by using current decoupling, and carrying out fault judgment according to the zero-module current and a fault pole selection criterion to obtain the fault type; (S5) finding out a fault pole according to the fault type, collecting a current signal ofthe fault pole and calculating a Kurtosis factor; and (S6) judging whether the fault appears in the line or not according to the Kurtosis factor and a Kurtosis factor criterion. According to the transfer entropy-based multi-terminal DC transmission line protection method, the problems of low practicability, a complicated system structure and a poor fault identification effect and the problem thatprotection cannot be carried out in an offline state in the prior art are solved.

Description

technical field [0001] The invention relates to the technical field of line protection, in particular to a method for protecting multi-terminal DC transmission lines based on transfer entropy. Background technique [0002] In the 1990s, the voltage source converter type high-voltage direct current transmission (VSC-HVDC) based on fully controlled devices developed rapidly. The emergence of VSC technology has also promoted the development of multi-terminal direct current transmission (MTDC), but the current two-level VSC and half-bridge modular multilevel converter (MMC) in multi-terminal direct current system engineering are more sensitive to DC line faults. Fault-induced voltage drops that cause overcurrent in insulated-gate bipolar transistors (IGBTs) may have more serious consequences. [0003] The development of multi-terminal DC transmission technology also makes the research of its protection scheme particularly important, but the accurate and selective removal of fau...

AI Technical Summary

Problems solved by technology

[0009] Aiming at the above-mentioned deficiencies in the prior art, the present invention provides a multi-terminal direct current transmission line protection method based on transfer entropy with high practicability, simple system structure, accurate fault identification effect an

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